Glass screw cap



Man ch 20,1945. H.C,'BUCHMAN 2372,156

GLASS SCREW cAP Filed May 21, 1942 @Z ZI'W I BY I fay! ATTORNEYS INVENPOR. Harry C. Buchmon.

Patented Man 20, 1945 UNITED STATES-PATENT OFFICE I 2,372,15 t GLASS EW CA Harry G. Buchman; Lanc aster, Ohio, assigngr to Anchor Hocking- Glass Corporation, Lancaster Ohio, a corporation of Delaware I I nne te 'M 1; I a1r9- ee a 's'olai s. (01.215543 tela sto lass sc ew ca It hit -t9. ea, mere art l rl t a no l sc ew tea 8 e re l n cat ime sc w cap r se ing Such a Ma n a s, arem f a, at 91 it! he sho ta e efm ta at h s-v se time th re i a nee o a la scr w a lat alsi a a eater cap Q c s a, umb r of be me hich. a e no c red t me a screwi apa n h fi st ad on the lass ca m be s t at wi lia a er mooth ur ace st th t t i lain and n h hr a er he.

glass fa? ch fiscall has a. f i l u h su a e 511}? t9 he tact th itis farm d b onta witl a i rc eld, artherncre the t read on ti li be ery acci it fo ed so th 11 ecrerat PIQDEIWWZW t e th ad are her: i v i v One of the objects of my invention'is to pro.- Y qt e screw can whic ll b o a ac EPQ nredeier ei e iiiHWMWI and wh ch W have an cc r te threa at pre eterm ned pitch .81 fi d. P A I Q lngthenohject of vmyinyention .is to provide a glass screw cap which will have a thread formed erecethat W li ave an extremely smooth face.

In its preferred form, my invention contemplates the provision of a screw cap made entirely of glass and of a suitable shape to fit the particular glass container upon which it is to be mounted. In this application, I disclose a glass lid of a type suitable for use on Mason jars. This lid comprises a substantiall disk-like upper portion having a depending peripheral flange. This peripheral flange has a screw thread formed on its inner surface for cooperating with the threaded mouth of the jar. This thread is accurately formed. Each convolution of the thread,

is of curved cross-section and the spaces between the convolutions are also of curved cross-section.

Thus, no sharp edges are present. Furthermore,

Fi r .2 i a s de e vatieaal vi w rar lr P F9 S3 wa shcwine th camera 99 a tamerieu e 1 a i i ar v ew .s l l a can, o

the t whe e. he are e ci we eece 99* as a i u ar We 9 d.

' The lid is formfd nt irely r glass and corn.-

' iiallv s i li-l keeeriie l ms Pe iph ral flan e, we arises aalttp'e i wh ch has e e a ha a'it i i 'ii 3 emcee dimen ona and sha f rmed an i eersur e n s he-t ead- .4 ce resee din h l cal rave ind cency i terme n the Outer surface of the flange but this groove or indenta: n has o 1. t 9 in th -rus 9f he ia 33 twf a' h e va tes 9 th heli a ead 3-, we a med 91% the nne su face 6? he'j a c In te mite t i erec e 4 Qui l-1e I inner surface, a edrrspoilding helical pro'je ion 4:; is formed on the outer surface. It will be noted from the drawing, especially Figures 3 and 4, that the cross-section of the thread 3 and the groove 4 is curved such that no sharp edges are provided. The inner surface of the flange 2 thus consists of gradually sweeping curved surfaces similar to corrugations. It is important to eliminate sharp edges from the inner surface of the flange so that the lid will not grind on the cooperatingportion of the jar 5. It will be noted that the jar shown has a threaded mouth portion 6 for cooperating with the thread 3. The surfaces of the thread 3 and the spaces 4 are extremely smooth so that they will not grind on the cooperating surfaces of the threads 6 on the jar which is usually formed in contact with an iron mold and consequently has a comparatively rough surface.

The glass lid I has its inner surface diverging outwardly slightly at its lower end, as indicated at I, so that it will readily telescope with the upper end of the jar. This diverging portion. is not threaded. Furthermore, a slight recess 8 is provided at the lower inner edge of the flange to facilitate telescoping of the lid over the jar. The extreme lower edge of the flange has a fairly sharp edge 9 formed thereon. As shown in Figure 3, this edge 9 is adapted to cooperate with a compressible sealing gasket II] which may be provided on a sealing ledge I I usually formed on a jar of this type. It will be noted that the flange of the cap is of such depth that the top I will not contact with the upper edge of the jar when the lower edge of the flange is in sealing contact with the gasket I0.

In some cases, it may be desirable for the lid to have a gasket-receiving annular groove Ila formed in the inner surface of the disk-like portion I adjacent its periphery, as shown in Figure 4. This groove can receive a gasket Ifla which will cooperate with the top edge of the jar to seal it.

The disk-like portion I of the lid may be provided with a corrugated or wavy edge I3 which will facilitate gripping of the cap in applying it to or removing it from the jar. It will also be noted from Figures 3 and 4 that the extreme lower portion I5 of the flange 2 is thicker than the remainder of the flange. This serves to make th portion I5 stronger which is desirable in case it is used as the sealing portion, in the manner shown in Figure 3. The upper edge of portion I5 is shouldered, as indicated at IB.

As shown in Figures 3 and 4, the top convolution I I of the groove 4 extends upwardly and outwardly into the portion I. This permits the thread 4 to be extended upwardly to a point Ila (Figure 2) approximately at the level of the lower surface of the top portion I.

When the glass lid is mounted on the jar, the unthreaded lower portion 1 is slipped over the upper end of the jar and the lid will telescope over the jar until the lowermost thread of the lid contacts with the uppermost thread on the jar. Then the lid can be threaded onto the jar in the-same manner as a metal lid. The thread on the inner surface of the lid will be accurately formed to a predetermined dimension and pitch. Furthermore, it will have an extremely smooth surface.

It will be apparent from the above description that I have provided a glass lid having many advantages. A number of these advantages have been specifically referred to and others will be apparent.

Having thus described my invention, what I claim is: a

1. A glass screw cap for containers, comprising a body, a peripheral flange depending from the body and terminating in a thickened reinforcing portion at its free edge, said flange having helical alternate projections and grooves formed in its opposite faces between the body and said thickened flange portion, said projections and grooves on said opposite faces being of different cross-sectional shape, the inner alternate helical projections and grooves being reversely curved and merging with one another to present smooth rounded surfaces and the outer spaced helical projection having straight coplanar outer faces, said internal groove adjacent the thickened reinforcing portion of said flange terminating in a substantially straight portion providing the inner wall of said thickened flange portion, said thickened reinforcing flange portion having a fiat outer face extending outwardly beyond and in a plane substantially parallel to the plane of said co-planar outer faces, said thickened reinforcing portion having an annular internal recess beyond said substantially straight portion, the base of said thickened reinforcing portion extending downwardly and inwardly in a straight line at a relatively sharp angle with relation to the flat outer face of the thickened portion and then upwardly and outwardly in a straight line at a different angle and terminating at the lower edge of said internal recess to provide a relatively sharp annular depending container seal-engaging projection. v

2. A glass screw cap according to claim 1 wherein the top surface of the body of said cap at the junctureof said body and peripheral flang is provided with a series of smooth-surfaced upstanding outward projections forming gripping surfaces for the cap.

3. A glass screw cap according to claim 1 wherein the body of said cap is of disk-like formation and wherein the under face of said formation is provided with a gasket-receiving annular groove spaced inwardly from said flange.

HARRY C. BUCHMAN. y. 

